Intravaginal tampons are in common use by women for the retention of fluids or menses discharged along the walls of the vagina during the menstrual cycle. The menstrual discharge, comprising endometrial cells, secretions and blood, is intermittent and takes place over hours and days. The blood and other matter exude following the line of gravity. Sometimes the flow is light, sometimes heavy. Intravaginal tampons are usually formed of absorbent materials such as cotton, rayon cellulose wading, synthetic sponge, cellulose fluff, synthetic fibres or combinations of these materials and compressed or moulded usually to a generally cylindrical configuration of a size to fit within the vaginal tract.
Tampons having an insertion end, a withdrawal end, a withdrawal cord and a central section extending therebetween are well known in the art. From the prior art, cylindrical shaped tampons are known having ribs defined by grooves, said ribs extending radially outwards. Such tampons are known for example from WO 02/078586, EP 0 422 660, US 2002/0157222, U.S. Pat. Nos. 5,592,725, 5,895,408, EP 1 108 408, US 2003/0208180, WO 00/53141 and EP 0 639 363.
Tampons with grooves in the longitudinal direction of the tampon are known in the art.
For instance, WO 02/078586 and WO 02/076357 disclose tampons having spirally shaped grooves. The outer surface of the tampons provided with spirally shaped, pressed longitudinal grooves describing a straight path in the longitudinal direction of said tampon. However, a disadvantage of such spirally-grooved tampon is that its absorption of fluid is generally insufficient and relatively slow, such that by-pass and leakage problems may occur after the tampon has been put into use.
EP 1 459 720 describes a vaginal tampon having sinusoidal grooves along the outer surface, separated by longitudinal ribs. The grooves and ribs in these tampons follow an undulating path in the longitudinal direction of the tampon, which shows a periodic pattern. More in particular, the grooves and ribs follow an undulating path, with alternating larger and smaller curvatures.
Grooved tampons are generally manufactured by bringing fibrous material between press jaws. In the prior art, pressing machines are known to have penetrating segments, which form ribs defined by grooves and which penetrate the absorbing material in essentially a radial direction, i.e. in a direction leading to the central axis of the tampon. As a result, the ribs extend radially outwards and their medians form an essentially straight line towards the central axis of the tampon. Such machines are known for example from EP 0 422 660 and EP 0 639 363.
A grooved tampon can be formed with the following steps: rolling up a length of a continuous fibrous web to form a generally cylindrical tampon blank with a circumferential surface; simultaneous radial pressing of narrow, strip-shaped sections of the circumferential surface of the tampon blank arranged in a spaced manner to form a number of longitudinal grooves which are separated from one another by relatively uncompressed longitudinal ribs which extend radially outwards from a relatively compressed core, the core being compressed to a smaller extent in the area of the recovery end of the tampon than in its remaining area; and pressing of outer ends of the longitudinal ribs radially inwards to form a soft, smooth circumferential surface, while the relatively uncompressed fibrous structure of the ribs is preserved.
However, a problem associated with the above-described tampons having sinusoidally-shaped grooves in the longitudinal direction is that their process of manufacture is complicated, showing a low efficacy, and involving considerable material loss. More in particular, a problem can occur during insertion and/or withdrawal of a tampon in and/or out of the pressing apparatus. Friction can occur between the tampon grooves and the pressing apparatus. Elements of the pressing apparatus may obstruct the tampon in its path out of the pressing apparatus. As a consequence thereof sinusoidally-shaped tampons grooves can at least partly be destroyed when taking the compressed tampons out of the pressing apparatus. Tampons with partly destroyed ribs and grooves are of lower quality, can not be commercialized and have to be thrown away. This implicates a substantial loss of material, inefficiency of the production system and considerable increase in production costs of the tampons. In addition, obstruction during insertion and/or withdrawal of the tampon out of the pressing apparatus is disadvantageous in view of rapid and mass production of these tampon products.
In view hereof, it is clear that there is a need in the art for a tampon, which overcomes one ore more of these problems of the prior art. More in particular, there is a need in the art for a tampon of which the manufacture process is improved. There is also a need in the art for a tampon having improved absorption capacity compared to spirally-grooved tampons known in the prior art.
It is therefore an object of the invention to provide a tampon with an improved configuration, which is easier and more cost effective to fabricate. More in particular, it is an object of the invention to provide a tampon, which can be easily retracted out of a pressing apparatus without substantially destroying the formed grooves and ribs of the tampon.
It is further an aim of the invention to provide a tampon of which the grooves and ribs do not describe a straight or periodic path in the longitudinal direction of the tampon.
The present invention further aims to provide a tampon having improved absorption capacity compared to spirally-grooved tampons known in the prior art.
It is further an aim of the invention to provide a tampon that is soft to the touch and therefore comfortable to insert into the body cavity.
The advantages of the present tampons will become clear to the persons skilled in the art from the description and the accompanying figures provided below.